Autonomic Nervous System I, II & III Questions and Correct Answers the Latest Update
3 views 0 purchase
Course
Autonomic Nervous System
Institution
Autonomic Nervous System
Which one of the following statements concerning the parasympathetic
nervous system is correct?
A. The parasympathetic system uses norepinephrine as a neurotransmitter.
B. The parasympathetic system often discharges as a single, functional system.
C. The parasympathetic division is involved in...
Autonomic Nervous System I, II &
III Questions and Correct Answers
the Latest Update
Which one of the following statements concerning the parasympathetic
nervous system is correct?
A. The parasympathetic system uses norepinephrine as a neurotransmitter.
B. The parasympathetic system often discharges as a single, functional system.
C. The parasympathetic division is involved in accommodation of near vision,
movement of food, and urination.
D. The postganglionic fibers of the parasympathetic division are long compared
to those of the sympathetic nervous system.
E. The parasympathetic system controls the secretion of the adrenal medulla.
✓ *The answer is C.* The parasympathetic system maintains essential bodily functions,
such as vision, movement of food, and urination. It uses acetylcholine, not
norepinephrine, as a neurotransmitter, and it discharges as discrete fibers that are
activated separately. The postganglionic fibers of the parasympathetic system are
short compared to those of the sympathetic division. The adrenal medulla is under
control of the sympathetic system.
Which one of the following is characteristic of parasympathetic stimulation?
C. Contraction of sphincter muscle in the iris of the eye (miosis).
D. Contraction of sphincter of urinary bladder.
E. Increase in heart rate.
✓ *The answer is C.* The parasympathetic nervous system is essential in maintenance
activities, such as digestion and waste removal. Therefore, increased intestinal
motility to facilitate peristalsis, relaxation of urinary bladder sphincters to cause
urination, and increased bronchial secretions result. Increase in heart rate is a
function of the sympathetic nervous system.
Which of the following is characteristic of the sympathetic nervous system?
A Discrete response to activation.
B. Actions mediated by muscarinic and nicotinic receptors.
C. Effects only mediated by norepinephrine.
D. Responses predominate during physical activity or when experiencing fright.
E. Subjected to voluntary control.
✓ *The answer is D.* The sympathetic nervous system is activated by "fight or flight"
stimuli. To achieve rapid activation of this system, the sympathetic nervous system
often discharges as a unit. The receptors that mediate sympathetic nervous system
effects on neuroeffector organs are α and β receptors. Because the sympathetic
nervous system is a division of the autonomic nervous system, it is not subject to
voluntary control and functions below conscious thought.
Patient presents with salivation, lacrimation, urination and defecation as side
effects of a medication. Which one of the following receptors mediates the
actions
of this drug?
A. Nicotinic receptors.
B. α Receptors.
C. Muscarinic receptors.
D. β Receptors.
✓ *The answer is C.* The muscarinic receptors of the parasympathetic nervous system
maintain essential body functions such as digestion and waste elimination. The
nicotinic receptors are a receptor for acetylcholine. It plays a major role in skeletal
muscles, ganglia and synthesis of catecholamines in the adrenal medulla. α and β
receptor are receptors for norepinephrine and epinephrine and activation
A soldier's unit has come under attack with a nerve agent. The symptoms
exhibited are skeletal muscle paralysis, profuse bronchial secretions, miosis,
bradycardia, and convulsions. The alarm indicates exposure to an
organophosphate. What is the correct treatment?
A. Do nothing until you can confirm the nature of the nerve agent.
B. Administer atropine, and attempt to confirm the nature of the nerve agent.
✓ *The answer is C.* Organophosphates exert their effect by irreversibly binding to
acetylcholinesterase (AChE) and, thus, can cause a cholinergic crisis. Administration
of atropine will block the muscarinic sites, but it will not reactivate the enzyme,
which will remain blocked for a long period of time. Therefore, it is essential to also
administer pralidoxime as soon as possible to reactivate the enzyme before aging
occurs. Administering pralidoxime alone will not protect the patient against the
effects of acetylcholine resulting from AChE inhibition.
A patient on a diagnostic test for myasthenia gravis would be expected to have
improved neuromuscular function after being treated with:
A. Donepezil.
B. Edrophonium.
C. Atropine.
D. Echothiophate.
E. Neostigmine.
✓ *The answer is B.* Edrophonium is a short-acting inhibitor of acetylcholinesterase
(AChE) that is used to diagnose myasthenia gravis. It is a quaternary compound and
does not enter the central nervous system. Donepezil, isoflurophate, and
neostigmine are also AChEs but with longer actions. Donepezil is used in the
treatment of Alzheimer disease. Echothiophate has some activity in treating open-
angle glaucoma. Neostigmine is used in the treatment of myasthenia gravis but is not
used in its diagnosis. Atropine is a cholinergic antagonist and, thus, would have the
opposite effects.
What is the mechanism of action of cocaine?
Examify | Smart Grades | Latest update
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller TestTrackers. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $19.49. You're not tied to anything after your purchase.
